5.9L bogging down in gear

[bigdaddygb]

Ok so I have a 1999 dodge ram 2500 4x4 with the 5.9L 360 gas motor. I just did plug, wires cap rotor, the camshaft pickup in the distributor ( puck with wire coming out of it under distributor cap) wired it according to TSB and even installed new wire separators, new coil, and new IAC on back of throttle body. Idles great no hissing or anything till i step on gas then i hear hissing but still idles great. Put it in gear and it bogs down like its getting flooded. I did a compression test and all are between 150-185 across all cylinders. I did do the intake manifold plenum gasket last year and it seems like everything I do to make it run better makes it worse. Any ideas guys would be helpful. Thanks.

p.s. I did install new fuel injectors and a fuel filter prior to doing the plugs and stuff and ran a fuel pressure test and it holds steady at 50psi even while in gear.

 

[dapepper9]

What injectors did you put in it? Where did you get them from?

 

[bigdaddygb]

they were 21lb injectors or 19 lb new injectors from autozone

 

[dapepper9]

Oe replacement for the truck from autozone?

 

[bigdaddygb]

https://www.autozone.com/fuel-delivery/fuel-injector/gp-sorensen-fuel-injector/221924_594834_0

 

[dapepper9]

Ok cool. I only jumped straight to that because it's rather common that somebody puts injectors in a truck and they're totally wrong and run like garbage.

One thing you can do is unplug the upstream 02 and see how it runs. It'll rule out the sensor and its effect on fueling. If you can do live data with anything, watching TPS is something else you can do

 

[bigdaddygb]

ok yeah i can watch live data on my otc scanner. I will take out o2 and see if any different.

 

[bigdodge]

Make sure the idle air control motor is working. Pretty typical problem with those

Sent from my Pixel 3 XL using Tapatalk

 

[bigdaddygb]

yeah already checked that. it's working. the original one was carbon stuck and when i pulled it out it pulled apart just as i got it free. so I didn't have any reference as to how far in or out it was. So I installed it fully seated and it had the horrible vacuum hiss.. i turned it out 2 turns 2 or 3 times till i could start it up and hear nothing, but when i step on it I hear that hissing again. I am going to recheck all the bolts on my intake. This really got worse after i did that lower plenum gasket repair. I was just thinking about that and figure why not. I thought about buying the Hughes intake and replace it with a one piece. Anyone else use it and have any input?

 

[dapepper9]

What do you mean when you say you turned it out 2 or 3 times?

Hughes intake is great when used with tuning and other mods

 

[bigdaddygb]

The little nipple in the IAC can be turned in or out. It says in the instruction to match it to what you have in now by pulling back plastic cover under neath that has a spring in it and then turning the plunger in or out to match what your original one had. Since I couldn't match it to mine since mine exploded when i got it out I started the truck with it as it came from the parts place. I kept hearing a hiss and was told by someone else the hiss is caused by the iac not closing all the way on startup. and yes my truck idled like crap. So I pulled back plastic piece with spring and turned it out 2 turns. And kept doing that till on start up it started as a hiss then stopped almost immediately. But as I rev it up I hear the his again and when i put it in gear the idle gets crappy again and when i step on the gas it like bogs down and has no power at all like I have a young overweight out of breath kid pushing it uphill..lol

 

[dapepper9]

Yeah.... you shouldn't touch the pintle at all actually. The pcm will set the idle motor to what it wants naturally and messing with it has actually been shown to damage them

 

[bigdaddygb]

just going off what the instructions said. and it never stopped hissing and running ruff even after 10 minutes of idling. That was when i started reading directions and fooled with it.

 

[dapepper9]

Yeah you gotta reset the pcm and let it do its thing. Probably not your issues but food for thought. I'd be more curious about tps and 02 condition

 

[bigdodge]

I know no one likes to go to the dealer but for the IAC there is no better option. I bought quite a few of these and the OEM, at least the last one I bought, shouldn't have to be adjusted and won't fly out if u start the truck with it out to see if it's working. From my experience with my 408 the pcv will cause problems with idle as well although mine is extra sensitive because of the cam but still worth changing to eliminate possibilities

Sent from my Pixel 3 XL using Tapatalk

 

[bigdaddygb]

i will hook up scanner to check tps and o2 sensor today. I have new exhaust from manifolds back. new high flow magna cat original barrel style muffler, all correct pipping new o2 sensors, because of this issue has been ongoing and still can't find why it's happening. Probably some stupid sensor that i am not looking at that is causing issue with cpu. this is why i love the older trucks....lol

 

[bigdaddygb]

checked all the bolts and all were tight. wonder if I have a bad head gasket.. not really getting water in oil like a blown gasket (milky brown) but maybe enough to bog motor down and burn off while running maybe?? i know my radiator is low on coolant.

 

[bigdaddygb]

did a pressure test on coolant system and it held fine under pressure so I wouldn't suspect a blown head gasket or leaking one. haven't checked live data yet.